It is well known that in crop harvesters which utilize a high-speed, rotary cutting cylinder which cooperates with a stationary shear bar, the position of the cutting edge of each knife on the cylinder with respect to the cooperating shear bar is critical if proper cutting is to be achieved with the most efficient use of energy resources. Thus, it is common practice to provide not only a suitable means for shiftably adjusting the shear bar itself toward or away from the periphery of the spinning cylinder, but also to provide for adjustment of each of the knives of the cylinder. Typically, such knife adjustment is provided at several spaced locations along the length thereof in order that spacing problems may be addressed and resolved at several spaced locations along the knife. Due to manufacturing variations and tolerance buildups, it is not at all unlikely that different points along each knife will need to be adjusted by different amounts in order to bring the cutting edges of the knife into proper cutting relationship with the shear bar. Thus, the essentially rigid knives must, to some degree, be capable of flexing slightly to accomodate the fact that one point along the length thereof may be closer to the axis of the cutting cylinder than another point at the next attaching location.
However, typical, conventional cyclinders utilize generally planar knives which are adjusted edgewise inwardly or outwardly in order to accomplish knife edge positioning. Such edgewise adjustment is satisfactory unless it becomes necessary for the edge at one attaching point to be closer to or farther away from the knife supporting structure than other attaching points of the knife. In such situations, the knives must be flexed to the appropriate degree in an edgewise action, generally within their own planes, in order to accomplish the differential positioning. Such edgewise flexing can be difficult to achieve, depending upon the hardness and other characteristics of the knife itself, and can produce undesirable stress in the knives, leading to early fatigue.